Some communication systems allow the user of a device, such as a personal computer, to conduct voice or video calls over a packet-based computer network such as the Internet. Such communication systems include voice or video over internet protocol (VoIP) systems. These systems are beneficial to the user as they are often of significantly lower cost than conventional fixed line or mobile cellular networks. This may particularly be the case for long-distance communication. To use a VoIP system, the user installs and executes client software on their device. The client software sets up the VoIP connections as well as providing other functions such as registration and authentication. In addition to voice communication, the client may also set up connections for other communication media such as instant messaging (“IM”), SMS messaging, file transfer and voicemail.
Mobile devices are commonly used to place voice over IP calls when a user of the device is driving. Such communication is aided by use of a hands free device which enables the user to concentrate on driving whilst a voice over IP call takes place.
With increasing mobile bandwidths, there is increasing interest in providing packet-based video calls via client applications running on mobile devices such as Internet-enabled mobile phones. These mobile devices comprise transceivers such as short-range RF transceivers operating on one or more unlicensed bands for accessing the Internet via wireless access points (e.g. of Wi-Fi access points of WLAN networks), and/or cellular transceivers operating on one or more licensed bands for accessing the Internet via a packet-based service of a cellular network such as GPRS (General Packet Radio Service) or HSPA (High Speed Packet Access).
Video calls take up a large amount of device and network resource, and it is not uncommon for video calls to fail or suffer reduced quality due to insufficient resource. To date attempts to solve this problem have focused on trying to hide such issues from a user as far as possible.